Converging Shock Experiments

Shock focusing by convergent channels is explored by use of the VTF. Different geometries are simulated, with an eye to existing experiments (validation) as well as to aid in the design of future experiments (prediction).

Converging Richtmyer-Meshkov Instability

The objective is to propose an idealized version of more complex physical phenomena occuring in Inertial Confinement Fusion (ICF) or Supernova among other things. Various simulations of the Richtmyer-Meshkov instability of an cylindrical interface shocked by a cylindrical converging shock are presented. The initial flow consists in a cylindrical interface (thermal equilibrium imposing the Atwood to , to ), surrounded by a cylindrical shock of initial Mach number . The flow behind the shock is given by Chisnell's approximate solution of self-similar converging shocks (JFM, 1998). The simulations are performed within the AMROC framework, using the WENO-TCD patch solver.

First, the axisymmetric case is studied (unperturbed interface) and exhibits a complex wave interaction process, to be compared to the planar case. Second, axial and azimuthal perturbations are added and the mixing of the two fluids resulting from the RMI is simulated in 3D.